摘要:
A preferred embodiment biosensor is a multi-layer micro-porous thin film structure. Pores in a top layer of the micro-porous thin film structure are sized to accept a first molecule of interest. Pores in a second layer of the micro-porous thin film structure are smaller than the pores in the top layer and are sized to accept a second molecule of interest that is smaller than the first molecule of interest. The pores in the second layer are too small to accept the first molecule of interest. The pores in the top layer and the pores in the second layer are sized and arranged such that light reflected from the multi-layer micro-porous thin film structure produces multiple superimposed interference patterns that can be resolved. In preferred embodiments, the multi-layer micro-porous thin film structure is a porous silicon thin film multi-layer structure formed on a silicon substrate, such as a silicon wafer. Specific and nonspecific binding can be detected with biosensors of the invention. The position of peaks in the Fourier transform of the reflection spectrum and the shift in peak amplitudes can be used to determine the presence and quantity of targeted biological molecules of interest.
摘要:
A preferred embodiment biosensor is a multi-layer micro-porous thin film structure. Pores in a top layer of the micro-porous thin film structure are sized to accept a first molecule of interest. Pores in a second layer of the micro-porous thin film structure are smaller than the pores in the top layer and are sized to accept a second molecule of interest that is smaller than the first molecule of interest. The pores in the second layer are too small to accept the first molecule of interest. The pores in the top layer and the pores in the second layer are sized and arranged such that light reflected from the multi-layer micro-porous thin film structure produces multiple superimposed interference patterns that can be resolved. In preferred embodiments, the multi-layer micro-porous thin film structure is a porous silicon thin film multi-layer structure formed on a silicon substrate, such as a silicon wafer. Specific and nonspecific binding can be detected with biosensors of the invention. The position of peaks in the Fourier transform of the reflection spectrum and the shift in peak amplitudes can be used to determine the presence and quantity of targeted biological molecules of interest.
摘要:
The invention provides an optical sensor for detecting chemical reaction activity, including, e.g., enzyme activity and catalytic or reactive molecule activity. An optical sensor of the invention includes a porous photonic film that produces a predetermined spectral reflectance response. In preferred embodiments, the film has a chemical coating (such as a hydrophobic layer) within its pores with an affinity for the reaction product(s) of the catalytic or otherwise reactive analyte A coating can also act as a protective layer in preferred embodiment. A thin substrate susceptible to reaction by at least one analyte of interest is on the surface of the thin film to block pores of the thin film. A method of detecting chemical reaction activity of the invention exposes the optical sensor to an analyte of interest, such as an enzyme or otherwise catalytic or reactive molecule. The optical sensor is subjected to light and the reflectivity spectrum of the optical sensor is monitored for a change indicative of reaction activity. Monitoring can include observation for a visible change or data acquisition via instruments such as a spectrometer for monitoring for a change in interferometric reflectance spectra.
摘要:
The invention provides an optical sensor for detecting chemical reaction activity, including, e.g., enzyme activity and catalytic or reactive molecule activity. An optical sensor of the invention includes a porous photonic film that produces a predetermined spectral reflectance response. In preferred embodiments, the film has a chemical coating (such as a hydrophobic layer) within its pores with an affinity for the reaction product(s) of the catalytic or otherwise reactive analyte A coating can also act as a protective layer in preferred embodiment. A thin substrate susceptible to reaction by at least one analyte of interest is on the surface of the thin film to block pores of the thin film. A method of detecting chemical reaction activity of the invention exposes the optical sensor to an analyte of interest, such as an enzyme or otherwise catalytic or reactive molecule. The optical sensor is subjected to light and the reflectivity spectrum of the optical sensor is monitored for a change indicative of reaction activity. Monitoring can include observation for a visible change or data acquisition via instruments such as a spectrometer for monitoring for a change in interferometric reflectance spectra.
摘要:
Methods and systems of the invention can determine the identity and quantity of analytes in a vapor. In preferred methods, a porous optical film is exposed to vapor which contains analyte. The porous optical film is heated and its optical response is monitored during heating. An optical response observed via heating can determine the identity and/or quantity of the analyte. In preferred embodiments, optical response during a thermal pulse is compared to a database of sensor responses that are characteristic of various analytes. Preferred methods are conducted a relatively low temperatures, for example below about 200° C. In preferred methods, a heating and cooling cycle produces a hysteresis curve in the optical response that is indicative of analytes. In preferred embodiments, a thermal reset pulse resets the porous optical film for later use and also provides an optical response that can be used for sensing.
摘要:
The present invention uses externally applied electromagnetic stimulus to control and heat porous magnetic particles and material associated with the particles. The particles contain magnetic material, such as superparamagnetic iron oxide and are infused with a material. Application of a DC magnetic field allows them to be moved with their infused material, and application of an AC RF electromagnetic field allows them to be heated with their infused material. The material can be infused into pores of the particles and the particles can also adhere to an aqueous droplet. The present invention also provides a multi-layer porous magnetic particle. The particle includes a host layer having pores sized to accept magnetic nanoparticles. Magnetic nanoparticles are infused within pores of the host layer. An encoding layer includes pores that define a spectral code. The pores in the encoding layer are sized to substantially exclude the magnetic nanoparticles. The encoding layer can also be a multi-layer, exhibiting, for example, a complex spectral code.
摘要:
A method for forming photonic particles, where the method includes the steps of preparing a porous photonic material layer, patterning a soluble polymer on the porous photonic material layer, leaving dividing portions of the material layer untreated, infusing the polymer into the material layer, and removing the dividing portions of the material to obtain the photonic particles.
摘要:
A system and method for free space, optical remote sensing of a potential threat agent using spectrally responsive sensor material. In one example the sensor material is formed by particles, which in one particular form are porous photonic crystals. The particles are dispersed into an area being monitored for the presence of the potential threat agent. A pair of lasers is used to generate optical light beams that are directed at the sensor particles after the particles have been dispersed. The light reflected by the sensor particles is then analyzed. The presence of the potential threat agent causes a shift in the spectral peak of light reflected from the sensor particles that can be sensed using photo detectors and a processing subsystem. The system can be tuned to remotely detect for specific chemical, biological or environmental agents that may be present within a given area.
摘要:
The measurement of the wavelength shifts in the reflectometric interference spectra of a porous semiconductor substrate such as silicon, make possible the highly sensitive detection, identification and quantification of small analyte molecules. The sensor of the subject invention is effective in detecting multiple layers of biomolecular interactions, termed “cascade sensing”, including sensitive detection of small molecule recognition events that take place relatively far from the semiconductor surface.
摘要:
A method for imaging leverages the fluorescence lifetime of a fluorescent Si-containing particle to distinguish from background fluorescence. A particle is introduced into tissue. An excitation light pulse is applied to excite luminescence from the fluorescent Si-containing particle. Time-gated measuring of a responsive luminescence signal identifies the particle. In preferred embodiments the particle is coated or encapsulated with an organic material. The fluorescence lifetime of particles can be controlled during manufacture, such as by oxidation levels, quenching treatments, or by aging. This permits introducing and using groups of particles in imaging that have unique lifetimes and multiple time gating can be used to identify different particles or to monitor the change in lifetime of a single set of particles as they respond to a biochemical stimulus. The particles can also be functionalized for affinity to particular tissues and can be loaded with treatment molecules.